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http://today.java.net/images/tiles/111-appfuse.gif Raible Designs' AppFuse runs best on Tomcat. They wrote an interesting post comparing standards-compliance and performance on Tomcat and other containers.
AXON Datacenters
http://axondatacenters.com/wp-content/uploads/2012/10/logo_2-300x96.jpg Axon Datacenters is datacenter offering virtual hosting, dedicated servers and cloud services powered by Tomcat and other open-source software via their servers page at Axon Servers.
Bonhams
http://www.bonhams.com/images/BonLogoGrey.jpg Bonhams is an auction house founded in 1793, running Tomcat and other open-source software, as detailed in this article from CIO Magazine.
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